Dynamic systems may include an electromagnetic transducer which converts kinetic energy from a vibration source to electrical energy. Such transducers can be used as an energy harvester. For example, as an energy harvester, the electromagnetic transducer transforms environmental vibrational energy to electrical energy which can be utilized to power an electronic device.
In addition to an energy harvester, an electromagnetic transducer may also be used as a sensor or an actuator. As a sensor the transducer can monitor the conditions of a dynamic system based on the vibrational energy being converted to electrical energy. As an actuator, the electromagnetic transducer further converts or translates the electrical energy to a mechanical motion.
Typically, the electromagnetic transducer is composed of a magnetic structure and a coil structure which move relative to one another. If the electromagnetic transducer is used as an energy harvester, the ambient kinetic energy moves the magnetic structure and the coil structure relative to each other. The relative movement causes a variation in the electromagnetic field, generated by the magnet structure, thereby generating electrical potential across the coil structure. If the electromagnetic transducer is utilized as both a sensor and a harvester, the variation in the generated electrical signal can be used to monitor the performance of the system. As an actuator, the electromagnetic transducer is coupled to a power source which injects electrical current in the coil structure. The electrical current interacts with the electromagnetic field created by the magnet structure. Such interaction generates an electromagnetic force which may move the coil structure respective to the magnetic structure.
Electromagnetic transducers are regularly employed in harsh environmental conditions that have high centrifugal acceleration, high axial and radial static displacements, torsional and tilting movements. For example, the electromagnetic transducers may be used in a car suspension, a helicopter lead-lag damper, railroad tracks, a bridge, etc. Accordingly, a transducer may be required to convert small vibration amplitudes and, at the same time, withstand static loads which have a higher amplitude than the vibration.
This section provides background information related to the present disclosure which is not necessarily prior art.